(a) Field of the Invention
This invention relates to an improved free piston engine used with an aircraft gas turbine engine and more particularly, but not by way of limitation, to a free piston engine used as a power augmentation device or PAD for increased engine performance. Also, the free piston engine can be used to power engine turbine accessories and using different types of fuel, due to its 20 to 1 compression ratio.
(b) Discussion of Prior Art
Heretofore, a typical aircraft turbine engine, such as a Pratt and Whitney JT8D, produces an average of 250 psi at the engine's stators. The subject invention is designed to produce an average of up to 500 psi at the engine's stators at high altitudes and using less fuel with increased engine thrust. This feature allows for cutting back of the fuel to the engine's combustors and allowing combustion air to be used for cooling the stators and turbine blades.